Intermittent fasting alleviates the neuropathic phenotype in a mouse model of Charcot–Marie–Tooth disease

Department of Anatomy and Cell Biology, College of Medicine, McKnight Brain Institute, University of Florida, Gainesville, FL 32610, USA
Neurobiology of Disease (Impact Factor: 5.2). 04/2009; DOI: 10.1016/j.nbd.2009.01.002

ABSTRACT Charcot–Marie–Tooth type 1A (CMT1A) neuropathies linked to the misexpression of peripheral myelin protein 22 (PMP22) are progressive demyelinating disorders of the peripheral nervous system. In this study we asked whether dietary restriction by intermittent fasting (IF) could alleviate the neuropathic phenotype in the Trembler J (TrJ) mouse model of CMT1A. Our results show that neuropathic mice kept on a five month long IF regimen had improved locomotor performance compared to ad libitum (AL) fed littermates. The functional benefits of this dietary intervention are associated with an increased expression of myelin proteins combined with a thicker myelin sheath, less redundant basal lamina, and a reduction in aberrant Schwann cell proliferation. These morphological improvements are accompanied by a decrease in PMP22 protein aggregates, and enhanced expression of cytosolic chaperones and constituents of the autophagy–lysosomal pathway. These results indicate that dietary restriction is beneficial for peripheral nerve function in TrJ neuropathic mice, as it promotes the maintenance of locomotor performance.

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